How can you fix valvetrain geometery problems?
10-15-2002, 05:33 PM
#1
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Car: 91 camaro
Engine: 383
Transmission: T56
How can you fix valvetrain geometery problems?
My valvetrian geometry is way off, I can see that the roller tips of the rockers are not centered on the valve tip, but are over to the left. I tried loosening the studs and moving the guideplates over, but the holes in the plates won't allow them to move enough to correct the problem. What should I do? The only thing I can think of is to take a drill to the guideplates and elongate the holes where the rocker studs go through. Or should I just leave it?? 
Help!!
Help!! 
10-15-2002, 05:35 PM
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Car: 1987 Monte Carlo SS
Engine: L98
Transmission: 200-4R
Axle/Gears: 7.625 10 bolt/3.73s
Pushrod lenght will change your valvetrain geometery. You could buy a checker to find what lenght is best.
10-15-2002, 05:46 PM
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Car: 4
Engine: 6
Transmission: 5
They are designed that way. They are not supposed to be centered. If they are a little off center, they will force the valve to rotate, which makes the seat last a whole lot longer since the same spot on the valve doesn't contact the same spot on the seat all the time.
10-15-2002, 06:02 PM
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Car: 91 camaro
Engine: 383
Transmission: T56
They are supposed to be off-center? My old rocker arms have a wear pattern on the roller tip that is off to one side. My machinist looked at them and told me I needed to fix it by scooting the guideplates over. How much are they supposed to be off-center?
And if they are a little bit off, how fast will it wear out my valve guides? I mean, can I leave it for the time being? I really need to get this car running.
And if they are a little bit off, how fast will it wear out my valve guides? I mean, can I leave it for the time being? I really need to get this car running.
10-15-2002, 06:13 PM
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Car: 4
Engine: 6
Transmission: 5
It doesn't hurt anything, as long as the entire tip of the rocker is still on the valve, it's OK. In no case will it wear out the guides. If the rocker pushed sideways on the valve, it will kill the guide; but the guide does not care at what point the force is applied to the valve stem, as long as it's straight down.
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